(A) IVD height was calculated from lateral X-rays of the L3/4, L4/5, and L5/6 IVD space (box). (B) Pre-operative comparisons between lumbar IVD levels by sex. Significant sex differences in IVD height were only observed at the L3/4 and L2/3 IVD. (C) The percentage change in the average IVD height across these three levels was significantly different from pre-operative baseline for 1x and 3x, but did not differ between males and females. (n=6–8, * p<0.05, *** p<0.001, **** p<0.0001 from baseline, p values for 2-way ANOVA effects shown below each graph).